hmmm... I wish I practiced throwing my voice a lot sooner than I did. I also wish I spoke more confidently (kinda goes hand-in-hand with the last point). Nothing helps more than practicing though, no matter what happens you're gonna be better the more you do it.
I used to cast alone quite a lot back then, I knew a lot less about the tactics within the game. So it helped me a lot nerding Quake for a while :)
According to zoot in this same thread june/july 2011 was the time when he started to cast, so this one must be the one of these. Thanks a lot, though it's kind of short :(